Several minimally-invasive medical interventional procedures make use of inflatable balloon structures to apply treatments to targeted areas within a body lumen. Such balloons are typically formed by bonding an extruded tubular material to an inflation or delivery lumen. Examples of procedures that may use such balloons include treatment of atherosclerotic plaque in the arterial vasculature, and delivery of therapeutic agents, such as sclerosants, into blood vessels for treatment of venous reflux or other conditions.
Some such devices include drug eluting balloons which may include a dissolvable therapeutic agent coated onto an outer surface of an expandable balloon. Such coatings may require a chemical, mechanical, thermal or other release mechanism to limit loss of the therapeutic agent during positioning of the balloon at a target site.
Other drug delivery catheters may be configured to inject an active agent into a blood vessel. In some cases, one or more expandable balloons may be placed proximally and/or distally from an injection point in order to retain the injected active agent in a targeted region of the vessel. Both the drug eluting balloon and the direct injection devices have drawbacks.
Few devices and method have been developed for improving the administration of liquid medical substances, such as sclerosing agents, into the veins or other body lumens. Thus, improved methods and devices for treating the vascular system and other body lumens are desired.